A closer look at cholesterol

Cholesterol can be a complex topic due to the prevalence (& stickiness!) of outdated information, but I'm going to provide you with the most up-to-date data, and I'll do my utmost to make this easy!

Here are a few things you will learn:

• Why do we need cholesterol?
• What is it, really?
• If not HDL and LDL, then what?
• Debunk outdated myths 
• Steps you can take to improve your cholesterol profile 

Why do we need cholesterol?
Cholesterol is made by all nucleated cells in the body, and it’s a fundamental component of cell membranes, helping to maintain fluidity and stability.  It is vital for vitamin D synthesis, it’s a precursor for the synthesis of steroid hormones (including testosterone, progesterone, estrogen, and cortisol), and it’s essential for the formation of bile acids, which are required for the digestion of fat-soluble nutrients. 

What is it, really? 
Cholesterol is a fat (lipid), therefore it’s not soluble in water. It has to be packaged into particles called ‘lipoproteins’ to enable it to travel in our blood. Each lipoprotein is part lipid and part protein, lipid on the inside and protein on the outside, which enables them to move effortlessly through our bloodstream.

Typically, whenever anyone mentions cholesterol, the next question is, what is your LDL or HDL… 

LDL are the low-density lipoproteins - they contain more fat than protein; therefore, they float in the same way fat floats to the top of an aqueous solution. Conversely, HDL are the high-density lipoproteins that contain more protein relative to their fat content; hence, they’re more dense.

Over the years, HDL and LDL have been categorized as good and bad, respectively, but…spoiler alert…there’s no such thing as good or bad cholesterol! The cholesterol being transported in both the HDL and the LDL is the same cholesterol.

To make it simple, think of cholesterol this way:
Think of lipoproteins as cars that transport cholesterol through your vascular system (the highway in this analogy) in your body. Cholesterol (found within the lipoproteins) is like the passengers inside these cars.
Previously, the common belief was that the number of passengers in the cars (the cholesterol and fat inside the LDL particles) was the main risk factor for the development of heart disease.
However, recent research indicates that it's the number and type of cars (different lipoprotein particles) that have the most significant potential impact on the health of the lining of our blood vessels.

If not HDL and LDL, then what?  Introducing apoB, a more accurate marker of risk
Now that we better understand how cholesterol travels throughout the body, you need to know one more crucial piece to get the whole picture.

• Every lipoprotein particle is encased by a larger molecule called an apoliprotein, so the lipoproteins travel in two main families: 
• apoB encases LDL particles, as well as VLDL & IDL particles
  
• apoA encases HDL particles

Therefore, apo-B provides a better measure of the total number of atherogenic particles in the blood making it a valuable tool for assessing cardiovascular risk as well as guiding preventive measures and treatment strategies.

In 2019, the European Society of Cardiology/European Atherosclerosis Society stated apolipoprotein B (apo-B) was a more accurate marker of cardiovascular risk than low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (HDL-C). (1), (2). I recommend talking with your provider about testing apoB levels moving forward. The higher your apoB, the greater your risk of heart disease.

If cholesterol is so essential, why is it associated with heart disease?
Reverting to the car and highway analogy, if you have a lot of cars (lipoproteins) on the road, there’s a greater chance of an accident - a car/cars could slam into the side of the road (the endothelial lining of the arterial wall), and this can initiate the process of plaque formation.

Myths we can now clarify and update for the future of our health:

Steps you can take to improve your cholesterol profile:

1. Prioritize your metabolic health
   There’s no official definition of the term metabolic health, but it’s typically defined by the absence of metabolic syndrome, i.e., the absence of high blood pressure, high blood sugar, excess fat around the mid-section, and elevated triglycerides (3).  If you have three or more of these symptoms, you have metabolic syndrome, which puts you at increased risk of cardiovascular disease (4), (5).
   
   Unfortunately, there are a lot of metabolically unhealthy people among us…the CDC estimates that 1 in 3 Americans has pre-diabetes (6).  Symptoms of blood sugar dysregulation are so common they’re sadly considered normal, they include:
   - a general sense of fatigue/exhaustion
   - energy crash in the afternoon
   - carb cravings
   - always hungry
   - sexual dysfunction
   - overweight
   - depression, anxiety, sense of overwhelm, irritability
   …it’s a lengthy list, and the real problem is these symptoms are incredibly common, however, common does NOT equate to normal!
   
   If you struggle with any of the above, it’s worth double-checking your blood sugar status.
   And, if, by chance, you’ve already checked, but you’ve been a little nonchalant about your slightly elevated HA1c (measure of your sugars over a 3-month period), I strongly recommend making changes to regulate your blood sugar ASAP!
   Regulating blood sugar involves improving your food choices (especially when it comes to carbohydrates), incorporating more exercise into your daily life, and managing stress levels.
   
   
2. Address your gastrointestinal health
   One of the main ways our body eliminates the cholesterol we don’t need is through our bowel movements.  This is how constipation can cause elevated cholesterol. The best fiber for lowering cholesterol is soluble fiber; it becomes a gel-like consistency in our intestines, and it binds with cholesterol and carries it out of the body (7).
   Our gut microbiome plays a vital role in regulating lipid metabolism. Recent studies have shown that gut microbiota is a critical environmental factor in the regulation of metabolism, contributing to the occurrence and development of many diseases, including cardiovascular disease. Study interventions, including the use of prebiotics, probiotics, fecal microbiota transplantation, and natural herbal medicines, have shown their efficacy in the treatment of hyperlipidemia (8), (9).
   
   
3. Check your thyroid function
   Thyroid hormone influences the regulation of lipid production, absorption, and metabolism. Your thyroid function has a direct effect on cholesterol levels; hypothyroid patients have increased cholesterol levels compared to those with normal thyroid function (10).  
   
   
4. Resolve chronic inflammation
   Chronic inflammation can lead to the oxidation of lipoproteins and can, therefore, promote atherosclerosis, increasing the risk of heart disease.

If you, or someone you know, would benefit from personalized advice about how to be proactive about heart health, please don’t hesitate to reach out for further guidance - my cardiometabolic transformation program may be just what you're looking for!

References:

1. Glavinovic, T., et al (2022). Physiological bases for the superiority of apolipoprotein B over low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol as a marker of cardiovascular risk”. Journal of American Heart Association, 11(20), doi: 10.1161/JAHA.122.025858
2. National lipid association’s “Advanced lipid testing” what you need to know. https://www.lipid.org/sites/default/files/advanced-lipid-testing-tear-sheet_0.pdf
3. Mayo clinic (2021).  What is metabolic syndrome.  https://www.mayoclinic.org/diseases-conditions/metabolic-syndrome/symptoms-causes/syc-20351916
4. Mottillo, S., et al, 2010. The metabolic syndrome and cardiovascular risk a systematic review and meta-analysis.  J Am Coll Cardiol. 2010 Sep 28;56(14):1113-32. doi: 10.1016/j.jacc.2010.05.034
5. Wallenfeldt, K. et al (2004). Aplipoprotein B/aplipoprotein A-1 relation to metabolic syndrome and change in carotid artery intima-media thickness during 3 years in middle-aged men.  Stroke, 35(1), 2248-52. doi: 10.1161/01.STR.0000140629.65145.3c
6. CDC (2022).  Pre-diabetes. https://www.cdc.gov/diabetes/basics/prediabetes.html
7. Soliman, G. A., (2019).  Dietary Fiber, atherosclerosis, and cardiovascular disease.  Nutrients, May 23; 11(5), 1155. doi: 10.3390/nu11051155
8. Xiaokang, J. et al (2021).  Impact of gut microbiota and microbiota-related metabolites on hyperlipidemia.  Frontiers in Cellular and Infection Microbiology, 11.  doi.org/10.3389/fcimb.2021.634780
9. Kenny, D. J. (2020).  Cholesterol metabolism by uncultured human gut bacteria influences host cholesterol level.  Cell Host & Microbe. doi: 10.1016/j.chom.2020.05.013
10. Pirahanchi, Y., Sinawe, H., Dimri, M. (2023).  Biochemistry, LDL cholesterol. StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing.  https://www.ncbi.nlm.nih.gov/books/NBK519561